Morphological and anatomical observations about Mariliasuchus amarali and Notosuchus terrestris (Mesoeucrocodylia), and their phylogenetical relationships with other South American notosuchians

The phylogenetic relationship of the notosuchians Mariliasuchus amarali (Campanian; Bauru Group) and Notosuchus terrestris (Santonian; Neuquén Group) is revised. Morpho-anatomical evaluation of Mariliasuchus in the current bibliography indicate close relationship with Notosuchus, while cladistic analysis either related Mariliasuchus to Candidodon itapecuruense (Albian/eo-Cenomanian; São Luis-Grajaú Basin), as part of the phylotaxon Candidodontidae, or to Comahuesuchus brachybuccalis (Santonian; Neuquén Group). Comparative study of specimens shows similarities on the palate, choanae, dentition, retroarticular process, and other structures from Mariliasuchus and Notosuchus, supporting the original classification as a Notosuchidae. Preliminary phylogenetic analysis sets these taxa as sister-groups. Reevaluation of a previously published phylogenetic analysis from other authors provides further support for the Mariliasuchus+Notosuchus clade. The current work indicates that Mariliasuchus is a Notosuchidae, refuting its allocation as a Candidodontidae. The influence of character construction and the definition of Notosuchia are discussed.